Rotatable assemblies, such as pulleys, are used in such automotive applications as drive belt idlers and drive belt tensioners. It is known, in general, to mold pulleys from a plastic material, as shown in the U.S. Pat. No. 4,177,685 to DeLancey. Pulley assemblies having a moldable plastic pulley with a ball bearing molded into the central hub of the pulley are also known. It is also known to provide a bearing to which a shield is joined as a unitized assembly. The U.S. Pat. No. 4,033,643 to Miller et al. shows a unitized bearing assembly having a shield 16 that is joined to an inner race 11 by snap fitting it into a groove 11A. The grinding of the groove 11A is an additional manufacturing step, and the precision with which shield 16 is radially and axially positioned relative to the bearing assembly depends on the precision with which the groove 11A is ground. While unitization of a rotatable assembly simplifies its shipping and installation, the necessity of additional and precisely controlled manufacturing steps generally adds expense. It would be desirable, therefore, to provide a rotatable assembly including a rotatable member, bearing and shield that was unitized prior to installation, but which did not require additional manufacturing steps to unitize it or precise positioning of the shield prior to installation.